PURPOSE: To let heat with a wiring layer escape effectively to a semiconductor substrate body, and to evaluate the lifetime of the electro-migration of the wiring layer accurately by forming the wiring layer in broad width onto an inter-layer insulating film as a layer for dissipating heat and forming another wiring layer onto the wiring layer through another inter-layer insulating film.

CONSTITUTION: A wiring layer 11, which corresponds to the wiring layer of a semiconductor device but it has width broader than the wiring layer, is formed onto a semiconductor substrate body 1 corresponding to the semiconductor substrate body of the semiconductor device as a layer for dissipating heat through an inter-layer insulating film 2 corresponding to the inter-layer insulating film of the semiconductor device. Another wiring layer 3 corresponding to the wiring layer of the semiconductor device is formed onto the wiring layer 11 as the layer for dissipating heat as a layer for evaluating the lifetime of electro-migration through another inter-layer insulating film 7 being extended while covering the wiring layer 11 and corresponding to the inter-layer insulating film of the semiconductor device. The wiring layer 3 has pads 5, 6 for connection.